High coverage genome of the Tyrolean Iceman reveals unusually high Anatolian Farmer ancestry

The Tyrolean Iceman, discovered in the Italian part of the Ötztal Alps in 1991, is known as one of the oldest natural human glacier mummies, directly dated to 3350-3120 calibrated BCE. Being one of the first ancient humans whose complete genome had been sequenced, the initial genetic data of this individual suffered from low genomic coverage and traces of modern-DNA contamination, limiting subsequent genetic analyses. To genetically investigate this individual in more detail, we have generated a new complete genome sequence at high genomic coverage (15.3x). We reveal insights into the genetic ancestry of this individual. In particular, we show that, contrary to analyses of the previous genome, no detectable Late Neolithic 'Steppe ancestry” is present in this individual, and that the Iceman has the highest Anatolian farmer ancestry among contemporaneous ancient European individuals in the fourth millennium BCE, suggesting that he may derive from a rather isolated Alpine population with limited gene flow from contemporaneous sources that typically harbour such ancestry. Phenotypic analysis of the newly generated genome reveals that the Iceman had a higher polygenic score for darker skin than any present-day European population but lighter skin than early Neolithic farmers and hunter-gatherers from Europe, and that he had risk alleles associated with male-pattern baldness, obesity, Type 2 diabetes and obesity-related metabolic disease. This confirms some of the phenotypic observations from the preserved mummified body, such as high pigmentation and could explain the absence of hair on his head.